![[Linked Image from thumbs2.imgbox.com]](https://thumbs2.imgbox.com/a6/f3/XfwBsXOH_t.jpg)
More than likely the >>54<< is an assembly number. Have you noticed it any other location??
![[Linked Image from thumbs2.imgbox.com]](https://thumbs2.imgbox.com/8a/7a/9qosrlS9_t.jpg)
These touchmarks are the preliminary proofmarks on the 1st pass which designate exactly the purpose of the tube:
Eagle Crown over G(Geschoss) denotes a solid projectile tube and Eagle(covered by a rib) Crown over S is a tube destined for Schrot(shot). These marks would have been applied whilst the components were singular pieces.
![[Linked Image from thumbs2.imgbox.com]](https://thumbs2.imgbox.com/dc/fa/MdW3lqww_t.jpg)
The touchmark of >>Crown over N(Nitro)<< coupled with >>Bl. G.<<, which is Blei Geschoss or Lead projectile.
None of these point to a maker as they are pure Zella - Mehlis Proof Facility marks, so research would have to focus on other such examples of P. Oberhammer and see exactly who he sourced from the majority of his wares.
Serbus,
Raimey
rse